Piezoelectric vibration device

Abstract

Provided is a superiorly reliable piezoelectric vibration device that prevents cracks in a sealing plate of the piezoelectric vibration device when an external electronic component element is joined to the sealing plate by metal bumps.　According to the present invention, six sealing plate connection electrode parts are provided to a lower surface of an IC chip (electronic component element), six electronic component element connection electrode parts 37a–37f that are to be respectively connected to the sealing plate connection electrode parts of the IC chip are provided to an electrode pattern 37 at an upper surface of a first sealing member (upper sealing plate) 3 where not opposite a piezoelectric vibration plate 2, none of the sealing plate connection electrode parts or the electronic component element connection electrode parts being positioned on a line that connects the centers of two opposite long sides of the IC chip, and metal bumps are used to respectively join the six sealing plate connection electrode parts of the IC chip and the six electronic component element connection electrode parts 37a–37f of the upper sealing plate 3.

Description

Piezoelectric Vibration Device

[0001] The present invention relates to a piezoelectric vibration device.

[0002] Conventionally, there has been a stacked piezoelectric vibration device in which a sealing plate is laminated and integrated onto a vibration plate, and electronic component elements such as IC chips are connected using metal bumps (see, for example, Patent Document 1). In detail, one main surface of a piezoelectric substrate including a vibration portion and an outer frame portion surrounding the periphery of the vibration portion is covered with a first sealing member to seal the vibration portion, and the other main surface of the piezoelectric substrate is covered with a second sealing member to seal the vibration portion, external electrodes to which electronic component elements are connected are provided on at least one of the first sealing member and the second sealing member, and the electronic component elements are connected to the external electrodes of the sealing member using metal bumps at six positions that overlap part or all of the outer frame portion of the piezoelectric substrate in a plan view, thereby forming a piezoelectric vibration device.

[0003] In recent years, this type of piezoelectric vibration device has become increasingly smaller, with devices being developed that are smaller than the electronic component elements such as IC chips to which they are connected. Furthermore, the variety of oscillation ICs that meet the required oscillation characteristics has also increased.

[0004] Patent No. 6737326

[0005] However, as piezoelectric resonator devices become smaller, electronic component elements such as ICs mounted on piezoelectric resonator devices also become smaller and more diverse. As piezoelectric resonator devices become smaller, the conventional configuration of electrically connecting electronic component elements to a sealing member of a piezoelectric resonator device using metal bumps is prone to cracking of the sealing member when connecting electronic component elements to the sealing member of a piezoelectric resonator device if the pressure applied during bonding is too strong, while the bonding strength is likely to be insufficient if the pressure applied is too weak. Therefore, to ensure bonding strength, stress caused by the pressure applied during bonding may concentrate in a specific area of ​​the sealing member, causing bending and cracking of the sealing member, potentially reducing the reliability of the piezoelectric resonator device. Therefore, it becomes necessary to bond the metal bumps in a position that does not adversely affect the sealing member.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a piezoelectric vibration device that is highly reliable by preventing cracking of the sealing plate when an external electronic component element is joined to the sealing plate of the piezoelectric vibration device using metal bumps.

[0007] In order to achieve the above object, a piezoelectric vibration device according to the present invention provides a piezoelectric vibration device in which a piezoelectric vibration plate is hermetically sealed by upper and lower sealing plates that cover the upper and lower surfaces of the piezoelectric vibration plate, and an electronic component element is electrically and mechanically joined to the upper surface side of the upper sealing plate by metal bumps, wherein the piezoelectric vibration plate has a substantially rectangular shape and comprises: a vibration portion that is rectangular in plan view and has a pair of excitation electrodes formed thereon; an outer frame portion that has an inner peripheral wall that is rectangular in plan view and surrounds the outer periphery of the vibration portion; a holding portion that connects the outer periphery of the vibration portion to the inner peripheral wall of the outer frame portion; and a cutout portion that is formed by cutting out the piezoelectric vibration plate in the plate thickness direction between the vibration portion and the outer frame portion; the upper sealing plate has substantially the same rectangular shape as the piezoelectric vibration plate, covers the upper surface of the piezoelectric vibration plate to seal the vibration portion, and the lower sealing plate has substantially the same rectangular shape as the piezoelectric vibration plate The electronic component element has a rectangular shape and covers the lower surface of the piezoelectric diaphragm to seal the vibration part. The electronic component element has a rectangular shape in a plan view that has a smaller area in a plan view than the upper sealing plate and the lower sealing plate. Six or more sealing plate connecting electrode portions are formed on the lower surface of the electronic component element to connect to the upper sealing plate. The six or more sealing plate connecting electrode portions are not located on a line passing through the center of each of the sides on which three or more opposing sealing plate connecting electrode portions of the electronic component element are formed. The upper surface of the upper sealing plate that does not face the piezoelectric diaphragm has six or more electronic component element connecting electrode portions to which the six or more sealing plate connecting electrode portions of the electronic component element are respectively connected. The metal bumps electrically connect the six or more sealing plate connecting electrode portions of the electronic component element to the six or more electronic component element connecting electrode portions of the upper sealing plate.

[0008] According to this configuration, the six or more sealing plate connection electrode portions are not located on a line passing through the centers of the sides of the electronic component element on which three or more opposing sealing plate connection electrode portions are formed, so the metal bump is not bonded at a position on a line passing through the centers of the sides of the rectangle of the electronic component element on which three or more opposing sealing plate connection electrode portions are formed, which is the lowest point of deflection due to pressure during bonding. This makes it possible to prevent the bonding strength of the metal bump from weakening, and furthermore, it is possible to distribute the stress due to pressure during bonding and prevent the stress from concentrating on one part of the upper sealing plate, thereby preventing cracking of the upper sealing plate.

[0009] Furthermore, when five or fewer sealing plate connecting electrode portions are joined to electronic component element connecting electrode portions, it is not possible to disperse stress because joining is not possible at two points in the center of the rectangular side of the electronic component element. In contrast, since six or more sealing plate connecting electrode portions are joined to electronic component element connecting electrode portions, when the electronic component element is joined to the upper sealing plate with metal bumps, the stress caused by the pressure during joining can be dispersed, preventing the stress from concentrating on one part of the upper sealing plate and preventing cracking of the upper sealing plate.

[0010] The six or more sealing plate connecting electrodes of the electronic component element may be formed on the periphery.

[0011] According to this configuration, by forming six or more sealing plate connection electrode portions of the electronic component element on the peripheral portion, the stress caused by the pressure when joining the electronic component element to the upper sealing plate using metal bumps can be effectively distributed.

[0012] The six or more sealing plate connecting electrodes of the electronic component element may be formed at least at three corners of the electronic component element and at two or more locations at the center of a pair of long sides.

[0013] According to this configuration, when the electronic component element is joined to the upper sealing plate with a metal bump, the stress due to pressure is greatest at the center of the long sides of the electronic component element. However, electrode portions for sealing plate connection can be formed at two or more locations on either side of the lines connecting at least three corners of the rectangle of the electronic component element and the centers of a pair of long sides, thereby dispersing the stress at the center of the long sides of the electronic component element.

[0014] In addition, the six or more electrode portions for connecting electronic component elements of the upper sealing plate are formed in a rectangular area in a plan view inside the inner wall of the outer frame portion of the piezoelectric vibration plate, and one or more electrode portions for connecting electronic component elements are formed in the shape of a floating island that is not connected to anything.

[0015] According to this configuration, six or more electronic component element connection electrodes are formed in a rectangular region in a plan view inside the inner peripheral wall of the outer frame of the piezoelectric diaphragm, making it possible to mount smaller electronic component elements. In this case, when bonding the electronic component element to the upper sealing plate using metal bumps, deflection in the rectangular region inside the inner peripheral wall of the outer frame of the piezoelectric diaphragm can be suppressed, thereby preventing stress concentration due to pressure during bonding, even when a smaller electronic component element is mounted. Furthermore, by forming one or more electronic component element connection electrodes of the upper sealing plate as floating islands that are not connected to anything and using these one or more electronic component element connection electrodes only for mechanical connection, it is possible to avoid crowding of the electronic component element connection electrodes, effectively suppressing deflection in the rectangular region inside the inner peripheral wall of the outer frame of the piezoelectric diaphragm, and preventing cracking of the upper sealing plate.

[0016] In addition, it is preferable that the width of the portion of the outer frame portion of the piezoelectric diaphragm that corresponds to the short sides of the rectangle is greater than the width of the portion that corresponds to the long sides.

[0017] With this configuration, the electrode portion for connecting the sealing plate and the electrode portion for connecting the electronic component element can be joined at a position close to the short side portion of the outer frame of the piezoelectric diaphragm, which is wider and stronger than the long side, thereby reliably preventing cracking of the upper sealing plate due to the stress of pressure during joining.

[0018] According to the present invention, when an electronic component element is bonded to a sealing plate of a piezoelectric vibration device using a metal bump, the stress caused by the pressure during bonding can be dispersed, preventing cracking of the sealing plate, thereby making it possible to provide a highly reliable piezoelectric vibration device.

[0019] 1 is a cross-sectional view showing a schematic configuration of a piezoelectric vibration device according to an embodiment of the present invention. FIG. 1 is a schematic plan view of the first main surface side of a first sealing member (upper sealing plate) of the piezoelectric vibration device of FIG. 1. FIG. 2 is a schematic bottom view of the second main surface side of the first sealing member of the piezoelectric vibration device of FIG. 1. FIG. 3 is a schematic plan view of the first main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 1. FIG. 4 is a schematic bottom view of the second main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 1. FIG. 5 is a schematic plan view of the first main surface side of a second sealing member (lower sealing plate) of the piezoelectric vibration device of FIG. 1. FIG. 6 is a schematic bottom view of the second main surface side of the second sealing member of the piezoelectric vibration device of FIG. 1. FIG. 7 is a schematic bottom view of an electronic component element (IC chip) connected to the piezoelectric vibration device of FIG. 1. FIG. 8 is a schematic plan view of the first main surface side of the first sealing member of a piezoelectric vibration device according to a second embodiment of the present invention. FIG. 9 is a schematic bottom view of an electronic component element (IC chip) connected to the piezoelectric vibration device of FIG. 11. FIG. 12 is a schematic plan view of the first main surface side of the first sealing member of a piezoelectric vibration device according to a third embodiment of the present invention. FIG. 13 is a schematic bottom view of an electronic component element (IC chip) connected to the piezoelectric vibration device of FIG. 11.

[0020] First Embodiment A piezoelectric vibration device according to a first embodiment of the present invention will be described in detail with reference to Figures 1 to 8. In the following first embodiment, a case will be described in which quartz crystal is used for the piezoelectric vibration plate. However, in the piezoelectric vibration device of the present invention, the material used for the piezoelectric vibration plate is not limited to quartz crystal as long as it generates piezoelectric vibrations.

[0021] As shown in Fig. 1, the piezoelectric vibration device 101 according to the first embodiment is configured to include a piezoelectric diaphragm 2, a first sealing member 3, a second sealing member 4, and an IC chip 5. In this piezoelectric vibration device 101, the piezoelectric diaphragm 2 and the first sealing member 3 are bonded together, and the piezoelectric diaphragm 2 and the second sealing member 4 are bonded together to form a package 12 that serves as a piezoelectric vibrator with a substantially rectangular parallelepiped sandwich structure. In addition, an IC chip 5 is mounted on the main surface of the first sealing member 3 opposite to the surface bonded to the piezoelectric diaphragm 2. The IC chip 5, which serves as an electronic component element, is a one-chip integrated circuit element that, together with the piezoelectric diaphragm 2, forms an oscillator circuit. Here, the first sealing member 3 and the second sealing member 4 correspond to the "upper sealing plate" and "lower sealing plate" of the present invention.

[0022] In the piezoelectric diaphragm 2, a first excitation electrode 221 is formed on one of the main surfaces, that is, a first main surface 211, and a second excitation electrode 222 is formed on the other main surface, that is, a second main surface 212. In the piezoelectric vibrating device 101, a first sealing member 3 and a second sealing member 4 are bonded to each of the two main surfaces (the first main surface 211 and the second main surface 212) of the piezoelectric diaphragm 2, thereby forming an internal space of the package 12, and a vibrating part 22 (see FIGS. 4 and 5 ) including the first excitation electrode 221 and the second excitation electrode 222 is hermetically sealed in the internal space.

[0023] The piezoelectric vibrating device 101 according to the first embodiment has a package size of, for example, 1.0 × 0.8 mm, and is designed to be compact and low-profile. In addition, in order to achieve the miniaturization, the package 12 does not have castellations, but rather uses through-holes (described later) to achieve electrode conduction.

[0024] Next, the piezoelectric vibration plate 2, the first sealing member 3, and the second sealing member 4 of the piezoelectric vibration device 101 will be described with reference to Figures 1 to 7. Note that the description here focuses on the individual components that are not joined together and are configured as individual components.

[0025] As shown in Figures 4 and 5, the piezoelectric diaphragm 2 is a piezoelectric substrate made of quartz crystal, and both of its main surfaces (first main surface 211 and second main surface 212) are formed as flat, smooth surfaces (mirror-finished). In the first embodiment, an AT-cut quartz crystal plate that performs thickness-shear vibration is used as the piezoelectric diaphragm 2. In the piezoelectric diaphragm 2 shown in Figures 4 and 5, both main surfaces 211, 212 of the piezoelectric diaphragm 2 are in the XZ' plane.

[0026] In this XZ' plane, the direction parallel to the short side (short side) of the piezoelectric diaphragm 2 is the X-axis direction, and the direction parallel to the long side (long side) of the piezoelectric diaphragm 2 is the Z'-axis direction. Note that AT-cut is a processing technique in which an artificial quartz crystal is cut at an angle of 35°15' around the X-axis relative to the Z-axis, one of the three crystal axes of the artificial quartz crystal: the electrical axis (X-axis), the mechanical axis (Y-axis), and the optical axis (Z-axis). In an AT-cut quartz plate, the X-axis coincides with the crystal axis of the quartz crystal. The Y'-axis and Z'-axis coincide with the axes inclined 35°15' from the Y-axis and Z-axis of the quartz crystal, respectively. The Y'-axis and Z'-axis directions correspond to the cutting direction when cutting the AT-cut quartz crystal plate. Note that the piezoelectric diaphragm 2 is not limited to the AT-cut quartz crystal plate described above; an SC-cut quartz crystal plate or a tuning fork-type vibrator may also be used.

[0027] The piezoelectric diaphragm 2 has a vibration portion 22 having a substantially rectangular shape in plan view and a pair of excitation electrodes (first excitation electrode 221, second excitation electrode 222) formed on both main surfaces 211, 212, respectively, an outer frame portion 23 having a rectangular shape in plan view and surrounding the outer peripheral wall of the vibration portion 22, a holding portion 24 that holds the vibration portion 22 by connecting the outer peripheral wall of the vibration portion 22 and the inner peripheral wall of the outer frame portion 23, and a cutout portion 25 formed by cutting out the piezoelectric diaphragm 2 in the plate thickness direction between the vibration portion 22 and the outer frame portion 23. In other words, the piezoelectric diaphragm 2 has a configuration in which the vibration portion 22, the outer frame portion 23, and the holding portion 24 are integrally provided. Here, the width of the outer frame portion 23 at a portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2 is formed larger than that of a portion corresponding to the long sides.

[0028] In the first embodiment, the holding portion 24 is provided at only one location between the vibrating portion 22 and the outer frame portion 23. Furthermore, the vibrating portion 22 and the holding portion 24 are formed thinner than the outer frame portion 23. Due to this difference in thickness between the outer frame portion 23 and the holding portion 24, the natural frequencies of the piezoelectric vibrations of the outer frame portion 23 and the holding portion 24 differ, thereby suppressing the propagation of vibrations excited in the vibrating portion 22. Furthermore, a space is formed by bonding the first sealing member 3 and the second sealing member to the piezoelectric diaphragm 2, and the space is sealed. Note that the location where the holding portion 24 is formed is not limited to one location, and it may be provided at two or more locations between the vibrating portion 22 and the outer frame portion 23.

[0029] The retaining portion 24 extends (protrudes) in the -Z' direction from only one corner of the vibrating portion 22, which is located in the +X direction and the -Z' direction. Because the retaining portion 24 is provided at a corner of the outer periphery of the vibrating portion 22, where the displacement of the piezoelectric vibration is relatively small, the piezoelectric vibration is prevented from leaking to the outer frame portion 23 via the retaining portion 24, compared to when the retaining portion 24 is provided at a portion other than the corner (the center of the side), and the vibrating portion 22 can be more efficiently vibrated. Furthermore, compared to when the retaining portion 24 is provided at two or more locations, the stress acting on the vibrating portion 22 can be reduced, reducing the frequency shift of the piezoelectric vibration caused by such stress and improving the stability of the piezoelectric vibration.

[0030] The first excitation electrode 221 is provided on the first main surface 211 side of the vibrating section 22, and the second excitation electrode 222 is provided on the second main surface 212 side of the vibrating section 22. Lead wiring (first lead wiring 223, second lead wiring 224) for connecting these excitation electrodes to external electrode terminals is connected to the first excitation electrode 221 and the second excitation electrode 222. The first lead wiring 223 is led out from the first excitation electrode 221 and connected to a connection bonding pattern 27 formed on the outer frame section 23 via the holding section 24. The second lead wiring 224 is led out from the second excitation electrode 222 and connected to a connection bonding pattern 28 formed on the outer frame section 23 via the holding section 24. In this way, the first lead wiring 223 is formed on the first main surface 211 side of the holding section 24, and the second lead wiring 224 is formed on the second main surface 212 side of the holding section 24.

[0031] Both main surfaces (first main surface 211 and second main surface 212) of the piezoelectric diaphragm 2 are provided with vibration-side sealing portions for bonding the piezoelectric diaphragm 2 to the first sealing member 3 and the second sealing member 4, respectively. The vibration-side sealing portion on the first main surface 211 includes a vibration-side first bonding pattern 251 for bonding to the first sealing member 3. The vibration-side sealing portion on the second main surface 212 includes a vibration-side second bonding pattern 252 for bonding to the second sealing member 4. The vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 are provided on the outer frame portion 23 and are formed in an annular shape in a plan view. The first excitation electrode 221 and the second excitation electrode 222 are not electrically connected to the vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252.

[0032] As shown in FIGS. 4 and 5 , the piezoelectric diaphragm 2 has five through holes formed between the first main surface 211 and the second main surface 212. Specifically, the four first through holes 261 are provided in the four corner regions of the outer frame portion 23, respectively. The second through hole 262 is provided in the outer frame portion 23, on one side in the Z′-axis direction of the vibration portion 22 (the −Z′ direction side in FIGS. 4 and 5 ). A connection bonding pattern 253 is formed around each of the first through holes 261. Furthermore, a connection bonding pattern 254 is formed on the first main surface 211 side around the second through hole 262, and a connection bonding pattern 28 is formed on the second main surface 212 side around the second through hole 262.

[0033] In the first through hole 261 and the second through hole 262, a through electrode for achieving electrical continuity between the electrodes formed on the first main surface 211 and the second main surface 212 is formed along the inner wall surface of each through hole. In addition, the central portion of each of the first through hole 261 and the second through hole 262 forms a hollow through portion that penetrates between the first main surface 211 and the second main surface 212.

[0034] In the piezoelectric diaphragm 2, the first excitation electrode 221, the second excitation electrode 222, the first escape wiring 223, the second escape wiring 224, the first bonding pattern 251, the vibration-side second bonding pattern 252, and the connection bonding patterns 253, 254, 27, and 28 can be formed by the same process. Specifically, these can be formed from base films formed by physical vapor deposition on both main surfaces 211 and 212 of the piezoelectric diaphragm 2, and bonding films formed by physical vapor deposition on the base films. In the first embodiment, Ti (or Cr) is used for the base films, and Au is used for the bonding films.

[0035] 2 and 3, the first sealing member 3 is, for example, a rectangular parallelepiped substrate formed from a single piezoelectric substrate made of quartz, and the second main surface 312 (the lower surface that is bonded to the piezoelectric diaphragm 2) of this first sealing member 3 is formed as a flat, smooth surface (mirror-finished). Note that it is preferable to use an AT-cut quartz similar to that used for the piezoelectric diaphragm 2 for the first sealing member 3 so that the thermal expansion coefficients of the two can be made the same, but other quartz cut plates, piezoelectric substrates, glass substrates, etc. may also be used.

[0036] 2, six electrode patterns 37 are formed on the first main surface 311 (top surface on which the IC chip 5 is mounted) of the first sealing member 3 that does not face the piezoelectric diaphragm 2, and these electrode patterns 37 are formed so that some or all of them are located on the periphery of a rectangular area R (the rectangular area indicated by the dashed dotted line in FIG. 2) that includes the mounting pads of the IC chip 5, and are used as electronic component element connecting electrodes 37a, 37b, 37c, 37d, 37e, 37f to which six sealing plate connecting electrodes of the IC chip 5, which will be described later, are respectively connected. Note that this rectangular area R is located inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2.

[0037] The six electrode patterns 37 are formed in the arrangement shown in Fig. 2. That is, two electrode patterns 37 are formed in a rectangular shape at a corner in the A2-B2 direction and a corner diagonally positioned in the A1-B1 direction, the other two electrode patterns 37 are formed in a deformed L shape at the center of one short side in the A2 direction of the first sealing member 3 and the center of the other opposing short side in the A1 direction, and the remaining two electrode patterns 37 are formed in a wavy parallel shape in plan view from the corner in the A2-B1 direction to the corner in the A1-B2 direction.

[0038] 2, which include the mounting pads for the IC chip 5, and are located inside the rectangular region R in a plan view inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2, and are arranged on the periphery of the rectangular region R. Specifically, the electronic component element connecting electrode portions 37a, 37c, 37d, and 37f are arranged at the four corners of the rectangular region R, the electronic component element connecting electrode portion 37b is arranged along the long side R1 (see FIG. 2) on the A2 side of the rectangular region R, offset in the B2 direction from the center of the long side R1, and the electronic component element connecting electrode portion 37e is arranged along the long side R2 (see FIG. 2) on the A1 side of the rectangular region R, offset in the B1 direction from the center of the long side R2.

[0039] Of the six electronic component element connecting electrodes 37a to 37f, electronic component element connecting electrodes 37a and 37f, and electronic component element connecting electrodes 37c and 37d are arranged so as to be aligned on the same line in the short side direction (A1-A2 direction) of rectangular region R, while electronic component element connecting electrodes 37b and 37e are not arranged on the same line in the short side direction (A1-A2 direction) of rectangular region R, and electronic component element connecting electrodes 37b and 37e are not located on the line connecting the centers of the two opposing long sides of rectangular region R. Here, electronic component element connecting electrodes 37a to 37f are arranged near third, fourth, and fifth through holes 322, 323, and 324 of first sealing member 3, which will be described later.

[0040] These electronic component element connecting electrodes 37a to 37f are bonded to the sealing plate connecting electrodes of the IC chip 5 by FCB (Flip Chip Bonding) using metal bumps (for example, Au bumps) 38 (see FIG. 1).

[0041] As shown in FIGS. 2 and 3 , the first sealing member 3 has six through-holes formed therein, each connected to one of the electrode patterns 37 located at each of the four corners and two electrode patterns 37 at the center of each of the opposing short sides, and penetrating between the first main surface 311 and the second main surface 312. Specifically, four third through-holes 322 are provided in the areas of the electrode patterns 37 at the four corners (corner portions) of the first sealing member 3. Fourth and fifth through-holes 323, 324 are provided in the electrode patterns 37 at the centers of the opposing short sides in the A2 and A1 directions in FIGS. 2 and 3 . The A1 and A2 directions in FIGS. 2, 3, 6, and 7 correspond to the −Z′ and +Z′ directions in FIGS. 4 and 5, respectively, and the B1 and B2 directions in FIGS. 2, 3, 6, and 7 correspond to the −X and +X directions in FIGS. 4 and 5, respectively.

[0042] In the third through hole 322 and the fourth and fifth through holes 323, 324, through electrodes for achieving electrical continuity between the electrodes formed on the first main surface 311 and the second main surface 312 are formed along the inner wall surfaces of the respective through holes. In addition, the central portions of the third through hole 322 and the fourth and fifth through holes 323, 324 form hollow through portions that penetrate between the first main surface 311 and the second main surface 312.

[0043] A sealing-side first bonding pattern 321 is formed on the second main surface 312 of the first sealing member 3 as a sealing-side first sealing portion for bonding to the piezoelectric diaphragm 2. The sealing-side first bonding pattern 321 is formed in a ring shape in a plan view.

[0044] Furthermore, on the second main surface 312 of the first sealing member 3, a connection bond pattern 34 is formed at each of the four corners (corner portions) of the third through hole 322. A connection bond pattern 351 is formed around the fourth through hole 323, and a connection bond pattern 352 is formed around the fifth through hole 324. Furthermore, a connection bond pattern 353 is formed on the opposite side of the long axis direction of the first sealing member 3 from the connection bond pattern 351 (A1 direction side), and the connection bond pattern 351 and the connection bond pattern 353 are connected by a wiring pattern 33. Note that the connection bond pattern 353 is not connected to the connection bond pattern 352.

[0045] In the first sealing member 3, the electrode pattern 37, the sealing-side first bonding pattern 321, the connection bonding patterns 34, 351 to 353, and the wiring pattern 33 can be formed by the same process. Specifically, these can be formed from an underlayer film formed by physical vapor deposition on the first and second main surfaces 311, 312 of the first sealing member 3, and a bonding film formed by physical vapor deposition on the underlayer film. In this embodiment, Ti (or Cr) is used for the underlayer film, and Au is used for the bonding film.

[0046] 6 and 7, the second sealing member 4 is, for example, a rectangular parallelepiped substrate formed from a single piezoelectric substrate made of quartz, and the first main surface 411 (the upper surface that bonds to the piezoelectric diaphragm 2) of this second sealing member 4 is formed as a flat, smooth surface (mirror-finished). Note that it is preferable to use an AT-cut quartz similar to that used for the piezoelectric diaphragm 2 for the first sealing member 3 so that the thermal expansion coefficients of the two can be made the same, but other quartz cut plates, piezoelectric substrates, glass substrates, etc. may also be used.

[0047] A sealing-side second bonding pattern 421 is formed on the first main surface 411 of this second sealing member 4 as a sealing-side second sealing portion for bonding to the piezoelectric diaphragm 2. The sealing-side second bonding pattern 421 is formed in a ring shape in a plan view.

[0048] Four external electrode terminals 43 for electrical connection to the outside are provided on the second main surface 412 (the outer lower surface that does not face the piezoelectric diaphragm 2) of the second sealing member 4. The external electrode terminals 43 are located at the four corners (corner portions) of the second sealing member 4, respectively.

[0049] As shown in FIGS. 6 and 7 , the second sealing member 4 has four through holes formed therein that penetrate between the first main surface 411 and the second main surface 412. Specifically, the four sixth through holes 44 are provided in the four corner regions of the second sealing member 4. In the sixth through holes 44, through electrodes are formed along the inner wall surfaces of the sixth through holes 44 to ensure electrical connection between the electrodes formed on the first main surface 411 and the second main surface 412. The central portions of the sixth through holes 44 form hollow through portions that penetrate between the first main surface 411 and the second main surface 412. In addition, on the first main surface 411 of the second sealing member 4, connection bonding patterns 45 are formed around each of the sixth through holes 44.

[0050] In the second sealing member 4, the external electrode terminals 43, the sealing-side second bonding pattern 421, and the connection bonding pattern 45 can be formed by the same process. Specifically, these can be formed from an underlayer film formed by physical vapor deposition on the first and second main surfaces 411, 412 of the second sealing member 4, and a bonding film formed by physical vapor deposition on the underlayer film. In this embodiment, Ti (or Cr) is used for the underlayer film, and Au is used for the bonding film.

[0051] As shown in Fig. 1, an IC chip 5 (oscillator circuit element), which is an electronic component element, is bonded to the upper surface of the first sealing member 3 using metal bumps 38. On the peripheral portion of the lower surface of the IC chip 5, six sealing plate connection electrodes 51a, 51b, 51c, 51d, 51e, and 51f are formed at positions facing the six electronic component element connection electrodes 37a, 37b, 37c, 37d, 37e, and 37f, respectively, as shown in Fig. 8. The sealing plate connection electrodes 51a to 51f are formed so as not to be positioned on the center line passing through the center of the edge on which the three opposing sealing plate connection electrodes of the IC chip 5 are formed. In this embodiment, the sealing plate connection electrode 51b and the sealing plate connection electrode 51e are formed offset from the center line. The sealing plate connecting electrodes 51a to 51f of the IC chip 5 are joined and electrically connected to the electronic component element connecting electrodes 37a to 37f of the first sealing member 3 by the FCB method using metal bumps 38.

[0052] 8, similarly to the electronic component element connecting electrode portions 37a-37f of the first sealing member 3, the sealing plate connecting electrode portions 51a-51f of the IC chip 5 are arranged at positions corresponding to the four corners of a rectangular region R (see FIG. 2) that includes the mounting pads of the IC chip 5 and is located inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2 in a plan view, with the sealing plate connecting electrode portion 51b being arranged offset in the B2 direction from the center of the long side R1 (see FIG. 2) on the A2 side of the rectangular region R, and the sealing plate connecting electrode portion 51e being arranged offset in the B1 direction from the center of the long side R2 (see FIG. 2) on the A1 side of the rectangular region R. Note that the closest distance between the sealing plate connecting electrodes 51a-51f is preferably 0.2 mm or less.

[0053] Furthermore, similarly to the electronic component element connecting electrodes 37a to 37f, among the sealing plate connecting electrodes 51a to 51f, the sealing plate connecting electrodes 51a and 51f, and the sealing plate connecting electrodes 51c and 51d are arranged so as to be aligned on the same line in the short side direction (A1-A2 direction) of the rectangular region R, while the sealing plate connecting electrodes 51b and 51e are not arranged on the same line in the short side direction (A1-A2 direction) of the rectangular region R. Note that, similarly to the electronic component element connecting electrodes of the first sealing member 3, the sealing plate connecting electrodes of the IC chip 5 are not positioned on the line in the short side direction that passes through the centers of the two opposing long sides of the rectangular region R.

[0054] In the piezoelectric vibration device 101 including the piezoelectric diaphragm 2, first sealing member 3, and second sealing member 4, the piezoelectric diaphragm 2 and the first sealing member 3 are diffusion-bonded with the first vibration-side bonding pattern 251 and the first sealing-side bonding pattern 321 overlapping each other, and the piezoelectric diaphragm 2 and the second sealing member 4 are diffusion-bonded with the second vibration-side bonding pattern 252 and the second sealing-side bonding pattern 421 overlapping each other, thereby producing the sandwich-structured package 12 shown in FIG. 1 . This hermetically seals the internal space of the package 12, i.e., the space housing the vibration unit 22. At this time, the above-mentioned connection bonding patterns are also diffusion-bonded with each other overlapping each other.

[0055] By joining the connection bonding patterns together, electrical conduction is achieved between the first excitation electrode 221, the second excitation electrode 222, the IC chip 5, and the external electrode terminal 43 in the piezoelectric vibration device 101.

[0056] Specifically, the first excitation electrode 221 is connected to the IC chip 5 via the first escape wiring 223, the junction between the connection junction pattern 27 and the connection junction pattern 353, the wiring pattern 33, the connection junction pattern 351, the through electrode in the fourth through hole 323, and the electrode pattern 37. The second excitation electrode 222 is connected to the IC chip 5 via the second escape wiring 224, the connection junction pattern 28, the through electrode in the second through hole 262, the junction between the connection junction pattern 254 and the connection junction pattern 352, the through electrode in the fifth through hole 324, and the electrode pattern 37, in that order.

[0057] In addition, the IC chip 5 is connected to the external electrode terminal 43 via the electrode pattern 37, the through electrode in the third through hole 322, the joint between the connection bonding pattern 34 and the connection bonding pattern 253, the through electrode in the first through hole 261, the joint between the connection bonding pattern 253 and the connection bonding pattern 45, and the through electrode in the sixth through hole 44, in that order.

[0058] Incidentally, when the sealing plate connecting electrode portions 51a to 51f of the IC chip 5 are bonded to the electronic component element connecting electrode portions 37a to 37f of the first sealing member 3 by the FCB method using the metal bumps 38, the stress due to the pressure during bonding is greatest at the center of the side of the rectangular region R (see FIG. 2) in plan view inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2, which includes the mounting pads of the IC chip 5. In particular, if the rectangular region R is rectangular, the stress is greatest at the center portion in the long side direction.

[0059] In the first embodiment, the two opposing sides of the rectangular region R are, for example, the opposing long sides of the rectangular region R, and are set along the sides (long sides of the IC chip 5) on which three or more opposing sealing plate connection electrodes of the IC chip 5 are formed. Furthermore, no electronic component element connection electrodes or sealing plate connection electrodes are arranged on the line connecting the centers of the two opposing long sides of the rectangular region R (the long sides of the rectangular region R along the long sides on which three or more opposing sealing plate connection electrodes of the IC chip 5 are formed), so bonding can be performed at locations other than the line connecting the centers of the two long sides of the rectangular region R. Therefore, in the long side direction of the rectangular region R where deflection is greatest, the bonding strength of the metal bumps is likely to weaken at the position of the lowest point of deflection (on the line connecting the centers of the two long sides). However, since bonding is performed while avoiding the lowest point of deflection, weakening of the bonding strength of the metal bumps can be suppressed.

[0060] Therefore, according to the first embodiment, none of the electronic component element connecting electrode portions or the sealing plate connecting electrode portions are located on the line connecting the centers of the two opposing long sides of the rectangular region R (see Figure 2) in a plan view inside the inner wall of the outer frame portion 23 of the piezoelectric diaphragm 2, including the mounting pads of the IC chip 5.Therefore, when the six sealing plate connecting electrode portions 51a to 51f and the electronic component element connecting electrode portions 37a to 37f are joined by the FCB method using the metal bumps 38, the metal bumps 38 are not joined at a position on the line passing through the centers of the opposing long sides of the rectangle of the IC chip 5, which is the lowest point of deflection due to pressure during joining.This distributes the stress during joining and prevents the stress from concentrating on a part of the first sealing member 3, prevents cracking of the first sealing member 3, and also suppresses a weakening of the joining strength of the metal bumps 38.

[0061] Furthermore, when the six sealing plate connection electrode portions 51a to 51f are joined to the electronic component element connection electrode portions 37a to 37f by the FCB method using metal bumps 38, the stress caused by the pressure applied during joining can be dispersed, preventing the stress from concentrating on a part of the first sealing member 3, and preventing cracks in the first sealing member 3 and poor joining strength.

[0062] Furthermore, since the six sealing plate connection electrodes 51a to 51f of the IC chip 5 are formed on the peripheral edge, the stress caused by the pressure when joining the IC chip 5 to the first sealing member 3 using the metal bumps 38 can be effectively dispersed.

[0063] In this case, by forming electrode portions 51a, 51c, 51d, and 51f for connecting the sealing plate at the four corners of the rectangular region R, it is possible to bond the IC chip 5 at the two diagonal portions and part of the long side, which correspond to the maximum width dimension when bonded, thereby suppressing displacement of the first sealing member 3 above the vibration portion 22 of the piezoelectric vibration plate 2.

[0064] Furthermore, the outer frame portion 23 of the piezoelectric diaphragm 2 is formed so that the width of the portion corresponding to the short side of the rectangle of the piezoelectric diaphragm 2 is larger than the portion corresponding to the long side. Therefore, the sealing plate connection electrode portions 51a to 51f of the IC chip 5 and the electronic component element connection electrode portions 37a to 37f of the first sealing member 3 can be joined at a position close to the short side portion of the outer frame portion 23 of the piezoelectric diaphragm 2, which is wider than the long side and stronger, thereby reliably preventing the first sealing member 3 from cracking due to the stress of pressure during joining.

[0065] Furthermore, the electrode portions 37a and 37f for connecting electronic component elements, the electrode portions 37c and 37d for connecting electronic component elements of the first sealing member 3, and the electrode portions 51a and 51f for connecting sealing plates, and the electrode portions 51c and 51d for connecting sealing plates of the IC chip 5 are arranged side by side on the same line in the short side direction (A1-A2 direction) of the rectangular region R shown by the dotted line in Figure 2, so that the stress caused by the pressing force during joining can be distributed evenly at multiple linear positions in the short side direction of the rectangular region R.

[0066] Furthermore, since the electrode portions 37a to 37f for connecting electronic component elements are positioned near the third, fourth, and fifth through holes 322, 323, and 324 of the first sealing member 3, the third, fourth, and fifth through holes 322, 323, and 324 of the first sealing member 3 can be used to relieve stress caused by pressing during bonding, thereby enhancing the stress dispersion effect.

[0067] Furthermore, by positioning the electronic component element connection electrodes 37a-37f of the first sealing member 3 inside the rectangular region R in a plan view, it becomes possible to mount a smaller IC chip (electronic component element) 5. This allows for the miniaturization of the piezoelectric vibration device. Furthermore, mounting a small IC chip 5 is expected to expose and make visible the electrode pattern 37 formed in a position overlapping the outer frame portion 23 of the piezoelectric vibration plate 2, making it easier to measure by reliably contacting the measurement terminal with this electrode pattern. Furthermore, by positioning the small IC chip 5 inside the rectangular region R, the area of ​​the surrounding area is reliably secured, preventing underfill or the like applied to the gap after mounting the IC chip 5 from overflowing from the edge of the piezoelectric vibration device 101, thereby stabilizing the application of the underfill.

[0068] Second Embodiment A piezoelectric vibrating device according to a second embodiment of the present invention will be described in detail with reference to Figures 9 and 10. The piezoelectric vibrating device according to the second embodiment differs from the first embodiment in the arrangement of the electrode pattern 37 of the first sealing member 3 and the electrode portions for connecting electronic component elements, and in the arrangement of the electrode portions for connecting the sealing plate of the IC chip 5, but is otherwise the same as the first embodiment. Below, differences from the first embodiment will be described with reference to Figures 1 to 8.

[0069] 9 , eight electrode patterns 37 are formed on the first main surface 311 of the first sealing member 3. Specifically, four electrode patterns 37 are formed at the four corners of the first main surface 311, one electrode pattern 37 is formed in the center of the long side in the A2 direction, one electrode pattern 37 extending in the A2 direction is formed in the center of the long side in the A1 direction, one electrode pattern 37 like a floating island that is not electrically connected to anywhere is formed in a position shifted in the B2 direction from the electrode pattern 37 at the center of the long side in the A2 direction, and one rectangular electrode pattern 373 is formed in a state of being electrically isolated via a rectangular cutout 374 in the electrode pattern 37 extending in the A2 direction at the center of the long side in the A1 direction.

[0070] These eight electrode patterns 37 are formed so that some or all of them are located on the periphery of a rectangular region R (similar to the rectangular region R indicated by the dashed dotted line in FIG. 2 ) that includes the mounting pads for the IC chip 5, as indicated by the dashed dotted line in FIG. 9 . Electronic component element connecting electrodes 37 a, 37 b, 37 c, and 37 d are arranged at approximately equal intervals along the long side of the rectangular region R in the A2 direction, electronic component element connecting electrodes 37 f, 37 g, and 37 h are arranged along the long side of the rectangular region R in the A1 direction, and electronic component element connecting electrode 37 e is arranged slightly offset in the A2 direction from the row of electronic component element connecting electrodes 37 f, 37 g, and 37 h. Note that this rectangular region R is located inside the inner circumferential wall of the outer frame portion 23 of the piezoelectric diaphragm 2.

[0071] 10 , sealing plate connecting electrode portions 51a, 51b, 51c, and 51d are formed at approximately equal intervals along the long side in the A2 direction on the bonding surface of the IC chip 5 with the first sealing member 3, facing the electronic component element connecting electrode portions 37a, 37b, 37c, and 37d, and sealing plate connecting electrode portions 51e, 51f, 51g, and 51h are formed at approximately equal intervals along the long side in the A1 direction so as to face the electronic component element connecting electrode portions 37e, 37f, 37g, and 37h. The sealing plate connecting electrode portions are formed so as not to be positioned on a center line passing through the center of the side on which the four opposing sealing plate connecting electrode portions of the IC chip 5 are formed. In this embodiment, the center line passes between sealing plate connecting electrode portion 51b and sealing plate connecting electrode portion 51c, and between sealing plate connecting electrode portion 51f and sealing plate connecting electrode portion 51g.

[0072] At this time, the eight electronic component element connecting electrodes 37a-37h of the first sealing member 3 are arranged inside a rectangular region R in plan view that includes the mounting pads of the IC chip 5 shown by the dashed dotted line in Figure 9 and is located inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2, and the eight sealing plate connecting electrodes 51a-51h of the IC chip 5 are similarly arranged, and the eight electronic component element connecting electrodes 37a-37h and the eight sealing plate connecting electrodes 51a-51h are bonded by the FCB method using metal bumps 38 (see Figure 1). Note that the metal bumps 38 that bond the electronic component element connecting electrodes 37d, 37g arranged on the floating island electrode pattern 37 and the sealing plate connecting electrodes 51d, 51g are used only for mechanical bonding.

[0073] Furthermore, the electronic component element connecting electrode portions 37a, 37h and the sealing plate connecting electrode portions 51a, 51h, the electronic component element connecting electrode portions 37b, 37g and the sealing plate connecting electrode portions 51b, 51g, the electronic component element connecting electrode portions 37c, 37f and the sealing plate connecting electrode portions 51c, 51f, and the electronic component element connecting electrode portions 37d, 37e and the sealing plate connecting electrode portions 51d, 51e are arranged side by side on the same line in the short side direction (A1-A2 direction) of the rectangular region R, and none of the electronic component element connecting electrode portions or the sealing plate connecting electrode portions are located on the line connecting the centers of the two opposing long sides of the rectangular region R. Here, all of the electronic component element connecting electrode portions 37a to 37h and the sealing plate connecting electrode portions 51a to 51h may be arranged symmetrically with respect to the line in the long side direction connecting the centers of the opposing short sides of the rectangular region R.

[0074] Therefore, according to the second embodiment, it is possible to obtain the same effects as in the first embodiment. Furthermore, because eight electronic component element connecting electrodes 37a to 37h and sealing plate connecting electrodes 51a to 51h are arranged on the first sealing member 3 and the IC chip 5, stress due to pressure during bonding can be distributed evenly at multiple linear positions in the short side direction of the rectangular region R in a plan view inside the inner peripheral wall of the outer frame portion 23 of the piezoelectric diaphragm 2, including the mounting pads of the IC chip 5, and cracking of the first sealing member 3 can be prevented.

[0075] Furthermore, since the electrode portions 37d, 37g for connecting electronic component elements are formed as floating island-like electrode patterns 37 that are not electrically connected to either, it is possible to avoid overcrowding of the electrode portions for connecting electronic component elements, effectively suppressing deflection in the rectangular region inside the inner wall of the outer frame portion 23 of the piezoelectric vibration plate 2, and preventing cracking of the first sealing member 3.

[0076] Furthermore, by forming sealing plate connecting electrodes 51a, 51d, and 51h at three corners of rectangular region R of IC chip 5, it is possible to join two diagonal portions corresponding to the maximum width dimension of IC chip 5 when joined and two locations on the long and short sides, thereby suppressing displacement of first sealing member 3 above vibration portion 22 of piezoelectric diaphragm 2. Furthermore, by forming sealing plate connecting electrodes 51b, 51c, 51f, and 51g at two or more locations in the center of the long sides of rectangular region R, it is possible to suppress the amount of deflection of the long sides of rectangular region R and thereby suppress deflection of first sealing member 3 above vibration portion 22 of piezoelectric diaphragm 2.

[0077] Third Embodiment A piezoelectric vibrating device according to a third embodiment of the present invention will be described in detail with reference to Figures 11 and 12. The piezoelectric vibrating device according to the third embodiment differs from the second embodiment in the arrangement of the electrode patterns 37 of the first sealing member 3 and the electrodes for connecting electronic component elements, and in the arrangement of the electrodes for connecting the sealing plate of the IC chip 5, but is otherwise the same as the second embodiment. Below, differences from the second embodiment will be described with reference to Figures 1 to 8, 9, and 10.

[0078] In the third embodiment, as shown in Fig. 11, instead of forming the electrode pattern 373 and the electronic component element connecting electrode portion 37g on the first sealing member 3 as in the second embodiment, seven electronic component element connecting electrodes 37a to 37f, 37h are formed on the first sealing member 3, and seven sealing plate connecting electrodes 51a to 51f, 51h are formed on the bonding surface of the IC chip 5 with the first sealing member 3, facing the electronic component element connecting electrodes 37a to 37f, 37h, respectively, as shown in Fig. 12. In this case, the sealing plate connecting electrodes are formed so as not to be positioned on the center line passing through the center of the sides of the IC chip 5 on which three or more opposing sealing plate connecting electrodes are formed. In this embodiment, the center line passes between the sealing plate connecting electrode portion 51b and the sealing plate connecting electrode portion 51c, and between the sealing plate connecting electrode portion 51f and the sealing plate connecting electrode portion 51h.

[0079] Therefore, according to the third embodiment, it is possible to obtain the same effect as in the second embodiment. Furthermore, by forming sealing plate connection electrode portions 51 a, 51 d, and 51 h at three corners of the rectangular region R of the IC chip 5 and forming sealing plate connection electrode portions 51 b, 51 c, and 51 f in two or more locations in the center of the long sides of the rectangular region R, it is possible to suppress displacement of the long sides of the rectangular region R and suppress deflection of the first sealing member 3 above the vibration portion 22 of the piezoelectric diaphragm 2.

[0080] The present invention is not limited to the above-described configuration, and various design modifications can be made within the scope of the claims.

[0081] For example, the piezoelectric diaphragm 2 in the above-described embodiment is not limited to an AT-cut quartz crystal plate, but may be an SC-cut quartz crystal plate or a tuning fork type vibrator.

[0082] In the above embodiment, the electronic component element is an IC chip 5, which is an oscillator circuit element. The IC chip can be a CMOS output oscillation IC, a differential output oscillation IC, a VCXO IC, a TCXO IC, or the like. Furthermore, the planar shape of the IC chip 5 is not limited to a rectangular one, and the present invention can also be applied to a square one. Furthermore, the electronic component element is not limited to an IC chip, and can be other electronic component elements such as a thermistor or a temperature sensor.

[0083] In addition, in the above-mentioned second embodiment, the case where two electrode portions 37d, 37e for connecting electronic component elements are arranged and formed in a floating island shape is described, but one or more electrode portions for connecting electronic component elements may also be arranged in a floating island shape.

[0084] In addition, in the above-mentioned embodiment, an example was given of a through electrode formed inside a through hole as a conductive path from the IC chip 5 to the external electrode terminal 43 of the second sealing member 4, but it is also possible to use a so-called castellation as a conductive path, in which a recess such as a notch is formed on the external end surface of the piezoelectric vibration device (first sealing member, piezoelectric vibration plate, second sealing member) 101 and a side end electrode is formed on the surface of the recess.

[0085] Furthermore, the shapes of the first and second excitation electrodes 221 and 222 are not limited to the rectangular shapes shown in FIGS. 4 and 5, but may be circular or polygonal.

[0086] The present invention can be widely applied to piezoelectric vibration devices in which a piezoelectric vibration plate is hermetically sealed by upper and lower sealing plates that cover the upper and lower surfaces of the piezoelectric vibration plate, respectively, and electronic component elements are electrically and mechanically joined to the upper surface of the upper sealing plate by metal bumps.

[0087] 2... Piezoelectric vibration plate 3... First sealing member (upper sealing plate) 4... Second sealing member (lower sealing plate) 5... IC chip (electronic component element) 22... Vibration portion 23... Outer frame portion 24... Holding portion 25... Cutout portion 37a to 37h... Electrode portion for connecting electronic component element 38... Metal bumps 51a to 51h... Electrode portion for connecting sealing plate 101... Piezoelectric vibration device 221... First excitation electrode 222... Second excitation electrode R... Rectangular area

Claims

1. A piezoelectric vibration device in which a piezoelectric diaphragm is hermetically sealed by upper and lower sealing plates that cover the top and bottom surfaces of the piezoelectric diaphragm, and an electronic component element is electrically and mechanically bonded to the top surface of the upper sealing plate by metal bumps, wherein the piezoelectric diaphragm has a substantially rectangular shape and comprises: a vibration section that is rectangular in plan view and has a pair of excitation electrodes formed thereon; an outer frame section that has an inner peripheral wall that is rectangular in plan view and surrounds the outer periphery of the vibration section; a holding section that connects the outer periphery of the vibration section to the inner peripheral wall of the outer frame section; and a cutout section that is formed by cutting out the piezoelectric diaphragm in the plate thickness direction between the vibration section and the outer frame section; the upper sealing plate has substantially the same rectangular shape as the piezoelectric diaphragm, and covers the top surface of the piezoelectric diaphragm to seal the vibration section; and the lower sealing plate has substantially the same rectangular shape as the piezoelectric diaphragm, and covers the bottom surface of the piezoelectric diaphragm to seal the vibration section; and the electronic component element is a piezoelectric vibration device having a rectangular shape in a plan view whose area in a plan view is smaller than those of the upper sealing plate and the lower sealing plate, and having six or more sealing plate connecting electrode portions formed on its lower surface which are connected to the upper sealing plate, the six or more sealing plate connecting electrode portions being not located on a line passing through the center of an edge on which three or more opposing sealing plate connecting electrode portions of the electronic component element are formed, the upper surface of the upper sealing plate not facing the piezoelectric vibration plate having six or more electronic component element connecting electrode portions to which the six or more sealing plate connecting electrode portions of the electronic component element are respectively connected, and the metal bumps electrically connect the six or more sealing plate connecting electrode portions of the electronic component element to the six or more electronic component element connecting electrode portions of the upper sealing plate, respectively.

2. The piezoelectric vibrating device according to claim 1, wherein the six or more sealing plate connecting electrodes of the electronic component element are formed on the periphery.

3. The piezoelectric vibration device described in claim 1, characterized in that the six or more sealing plate connection electrode portions of the electronic component element are formed in at least two locations: at least three corners of the electronic component element and the center of a pair of long sides.

4. A piezoelectric vibration device as described in any one of claims 1 to 3, characterized in that the six or more electrode portions for connecting electronic component elements on the upper sealing plate are formed in a rectangular area in a plan view inside the inner wall of the outer frame portion of the piezoelectric vibration plate, and one or more electrode portions for connecting electronic component elements are formed in the shape of a floating island that is not connected to anything.

5. A piezoelectric vibration device according to any one of claims 1 to 3, or claim 4 dependent on claim 1, characterized in that the width of the portion of the outer frame of the piezoelectric vibration plate corresponding to the short sides of the rectangle is greater than the width of the portion corresponding to the long sides.

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